“This hearing will be an important opportunity to shed light on critical consumer data privacy issues and help all Americans better understand what happens to their personal information online,” the pair said.

Cambridge Analytica is a political consulting firm that worked for US President Donald Trump’s campaign.

‘Breach of trust’

Facebook, which has two billion users. is now one of the main ways politicians connect with voters. It has been looking to repair its public image and restore users’ trust since the Cambridge Analytica story emerged.

Facebook said last month that it had hired forensic auditors to examine if Cambridge Analytica still had the data.

Mr Zuckerberg has apologised for a “breach of trust”, and taken out full-page advertisements in several UK and US Sunday newspapers.

He has also said he welcomes more regulation.

The US Senate commerce and judiciary committees also have requested that Mr Zuckerberg appear in front of them.

And the US Federal Trade Commission is investigating whether Facebook engaged in unfair acts that caused substantial injury to consumers.